Air flow directors of various types are well-known for vehicles such as automobiles and trucks. Such devices include front and rear body-mounted airfoils like inverted wings, rear- and roof-mounted spoilers or air dams, and bottom-mounted skirts. Such aerodynamics shapers and ground effects equipment have become popular on racing vehicles for increasing road contact at high speeds and for imparting greater stability. Their appeal has spread to sports car enthusiasts in the general public, so that airfoils, spoilers and skirts are now utilized for aesthetic and cosmetic purposes on many road vehicles, even in the absence of any aerodynamic requirement.
In the early 1960's, Ferrari's entry to the championship sports car racing courses included the sleek looking rear-engined 250P which had an integral, inverted U-shaped roll bar (sometimes called "anti-roll bar") or band extending laterally across the rear of the cockpit, just behind the driver's seat, and which also acted as an air slot to steady airflow over the rear deck. In 1963, the improved handling and road holding capabilities of the 250P made it "unrivalled among its contemporaries." It won three of the four major events counting towards the Manufacturer's World Championship in its class: the Sebring, the Nurburgring and the LeMans. (It only lost the Targa Florio to Porsche because it was driven off the road.) See, A. Harding, Cars in Profile: Collection 1, Doubleday & Co. ed. 1974, page 7.
An integral roll bar has become fashionable even for off-track sports cars. The 911 Targa body style, which was introduced by Porsche in 1965 and has remained popular since, features an all-steel form body structure welded into a single-unit body chassis that has an inverted U-shaped roll bar connecting its two sides across the rear of the passenger compartment at the location of the back of the front seats. The 911 style also featured a removable roof. The first cars had zip-out back windows like those of normal convertibles, but problems caused Porsche to go to a less sporty, fixed, glass rear window. See, D. Batchelor, Illustrated Porsche Buyer's Guide, Motorbrooks Int'l 1982, pages 70-77. Such integral roll bar construction has also been introduced into other manufacturer's automobiles as, for example, the Fiat X1/9 (designed by the same people who designed the Ferrari) and removable roof panel versions of the Corvette (with or without a "T-bar" centerline strut). Integral roll bars of the type under discussion are commonly referred to in the automobile trade as "Targa" bars or bands, regardless of which brand automobile is being referenced.
Targa bands, by virtue of their very roll bar nature and origin, are integral welded components of the associated vehicle body structure.
Conventional automobile Targa bands are bow-like structures of continuous truncated arcuate contour that stretch laterally from side-to-side over the rear of the passenger compartment. They have opposite pillar portions which reach upwardly and inwardly from lower ends that join the left and right sides of the rest of the body at positions generally located between the rear edges of the front doors and the front area (rear window connecting area) of the rear deck, to inwardly rounded upper ends which are connected together by a generally horizontally disposed, elongated central portion. In a usual configuration the band is relatively thin, with a width (front-to-back dimension) that is mostly uniform across the central portion but decreases slightly from lower to upper ends in the pillar portions. The width of the central portion is relatively greater than its thickness. The band is usually, though not necessarily, oriented to give it a slight backwardly tilted appearance when viewed from the side, with front and rear edges of the band at the upper ends of the pillar portions being respectively located to the rear of the same edges at the lower ends of the pillar portions. The height (vertical dimension) of the band is normally such as to coincide with the height of the front windshield, to place the top surface of the band generally in line with the header of the windshield, and the band is smoothly contoured and lined to match the contour and lining of the rest of the vehicle body.
The back of the Targa band customarily serves as part of the framework for a straight or sweptback window. The front of Targa-type bands of automobiles, such as Corvettes, is sometimes equipped in its central portion with a front edge lip recess or otherwise configured to accommodate the trailing edges of one or more removable roof panels. The windshield header is configured to receive the leading edges of such panels, and a longitudinal centerline strut extending between the header and the front of the Targa band (providing a "T" configuration) may provide additional roof top panel support. The front edges of the pillar portions of the band may be configured to provide guideways for the trailing edges of the front door side windows.
Conventional automobiles with removable tops are currently either of the Targa band, removable roof panel type or of the conventional convertible top type with folding flexible material top and/or removable hardtop options. They are not both.
Vehicles with folding convertible tops have flexible decking material stretched over a retractable frame comprising front, central and rear bows. The bow framework may be completely removable but, more commonly, folds back after release from the front windshield header into a storage position in the well behind the seats of the passenger compartment at the front of the trunk space or, as is done in recent model Corvettes, folds down into a storage cavity at the rear of the passenger compartment which is covered by a rear deck lid.
The term "hardtop" is the name given to a roof construction in which the usual central or B-pillar roof-supporting posts (which on four-door sedans are situated between the front and rear doors) are missing so that the roof is supported only by the A-pillars which frame the sides of the front windshield and by the C-pillars which frame the sides of the rear windshield Mercedes 280SL, 350SL and similar sports cars have a removable hardtop option that provides the advantages of a convertible top with the greater durability of a hard canopy.
With both convertible folding or "rag" tops and convertible removable hardtops (both collectively hereinafter referred to as "convertible tops"), means including slots or openings peripherally of the passenger compartment are provided to releasably lock protruding pins or similar elements of the removable top in its passenger compartment covering position. Typically the vehicle body of a convertible top automobile will have a recess located at each upper corner of the front windshield, a recess located at the corner of each side of the rear of the passenger compartment, and a recess located centrally at the rear of the passenger compartment at the front of the rear deck. The convertible top pins are fit into the recesses and releasably locked therein by quarter-turn T-bolt or other locking mechanisms to retain the same in place.
Convertible top automobiles operated with the top folded or removed have a rectangular box-like, generally horizontal upper profile when viewed from the side, interrupted only by the swept back vertical projection of the front windwhield at the front of the passenger compartment. The aesthetically pleasing effect of the integral Targa band roll bar structure, available only with removable top panels and not convertible tops, is absent. Moreover, the passenger compartment of the folded or removed convertible top automobile is completely open except for the windshield, thereby permitting uncontrolled entry of turbulent air flows that can cause passenger discomfort or at least disheveled appearance.